The cardenolides are a group of cardio-active steroids characterized by the presence of a 14.beta.-hydroxyl function and a 17.beta.-butenolide moiety ("Steroids", L. F. Fieser and M. Fieser, Reinhold Publishing Corporation, New York, New York, 1959, ch. 20). Many of these compounds, which occur in small amounts in various plants, are potent cardiac stimulants (G. K. Moe and A. E. Farah, in "The Pharmacological Bases of Therapeutics", 4th Ed., L. S. Goodman and A. Gilman, ed., The Macmillan Company, New York, N.Y., 1970, ch. 31), and for this reason, considerable synthetic effort directed toward their synthesis has been expended in the past. Prior to 1962, the fruits of these labors have been minimal. While methods for the introduction of the 14.beta.-hydroxy group and the construction of the 17.beta.-butenolide have been developed utilizing model compounds, they have been uniformly inapplicable in the natural series. In 1962, the problems associated with the configurational instability of the 17.beta.-butenolide and the lability of the 14.beta.-hydroxy function during construction of the butenolide were resolved in the first reported synthesis of a cardenolide, digitoxigenin. This synthesis, while recognized as a scientific breakthrough, suffers from the disadvantage of starting from difficultly available materials resulting in low overall yields (R. Deghenghi, Pure and Appl. Chem. 21, 153 [1970]). Since 1962, improved synthesis of cardenolides have been reported. These syntheses, like the original synthesis of digitoxigenin, however, start with preformed steroids, involve the direct introduction of the 14.beta.-hydroxyl group and suffer from the predominant disadvantage of the unavailability of the precursor steroids. Thus, an efficient synthesis of 14.beta.-hydroxysteroidyl cardenolide precursors, making ultimate cardenolides readily available for therapeutic use, would be a major advance in this area (P. J. Sykes and S. J. Whitehurst, in "Terpenoids and Steroids", K. H. Overton, ed., Volume 5, The Chemical Society, London, England, 1975, page 354).